Z-filter media pack arrangement; and, methods

ABSTRACT

Z-filter media pack arrangements and methods for providing them are described. The preferred arrangements have a cured-in-place jacket around an outside of a coiled z-filter media combination. The preferred cured-in-place jacket is a mold-in-place overmold which includes, integral therein, a housing seal arrangement. Preferably a cured-in-place center core is used, most preferably one that has opposite concave ends with seal arrangements configured to seal a lead end portion of the coiled z-filter media combination.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. Ser. No.13/572,796, filed Aug. 13, 2012, which has now issued as U.S. Pat. No.8,518,141; which was itself a continuation of U.S. Ser. No. 13/079,118,filed Apr. 4, 2012, which issued as U.S. Pat. No. 8,241,383. U.S. Ser.No. 13/079,118 is a continuation application of U.S. Ser. No.11/629,033, which issued as U.S. Pat. No. 7,967,886. U.S. Ser. No.11/629,033, was filed Dec. 7, 2006, as a National Stage ofPCT/US2005/019777, filed Jun. 6, 2005 with a claim of priority to U.S.Ser. No. 60/578,482 (a U.S. provisional application) filed Jun. 8, 2004.A claim of priority to each of U.S. Ser. No. 13/572,796; U.S. Ser. No.13/079,118; U.S. Ser. No. 11/629,033; PCT/US2005/019777; and, U.S.provisional patent application Ser. No. 60/578,482 is made to the extentappropriate. The complete disclosures of U.S. Ser. No. 13/572,796; U.S.Ser. No. 13/079,118; PCT/US2005/091777; U.S. Ser. No. 11/629,033; and,provisional patent application 60/578,482 are incorporated herein byreference.

The present application is a reissue application of U.S. Pat. No.9,114,346 issued on Aug. 25, 2015, which issued from U.S. applicationSer. No. 13/975,880, filed Aug. 26, 2013. U.S. application Ser. No.13/975,880 is a continuation of U.S. application Ser. No. 13/572,796,filed Aug. 13, 2012, which issued as U.S. Pat. No. 8,518,141 on Aug. 27,2013. U.S. application Ser. No. 13/572,796 is a continuation of U.S.application Ser. No. 13/079,118, filed Apr. 4, 2012, which issued asU.S. Pat. No. 8,241,383 on Aug. 14, 2012. U.S. application Ser. No.13/079,118 is a continuation of U.S. application Ser. No. 11/629,033,filed on Jun. 6, 2005, which issued as U.S. Pat. No. 7,967,886 on Jun.29, 2011. U.S. application Ser. No. 11/629,033 was filed fromPCT/US2005/019777, filed Jun. 6, 2005, with a claim of priority to U.S.provisional application 60/578,482 filed Jun. 8, 2004. A claim ofpriority to each of U.S. application Ser. Nos. 13/975,880; 13/572,796;13/079,118; 11/629,033; PCT/US2005/019777; and 60/578,482 is made to theextent appropriate. The complete disclosures of U.S. application Ser.Nos. 13/975,880; 13/572,796; 13/079,118; 11/629,033; PCT/US2005/091777;and 60/578,482 are incorporated herein by reference.

FIELD OF THE DISCLOSURE

The present disclosure relates to filter media for use in filteringliquids or gases. The disclosure particularly relates to media packsthat use z-filter media which comprises a corrugated media sheet securedto facing sheet, formed into a media pack. Specifically, the disclosurerelates to formation of such media packs and their inclusion inserviceable filter cartridge arrangements, typically for use in aircleaners. Methods of assembly and use are also described.

BACKGROUND

Fluid streams, such as air and liquid, can carry contaminant materialtherein. In many instances, it is desired to filter some or all of thecontaminant material from the fluid stream. For example, air flowstreams to engines (for example combustion air) for motorized vehiclesor for power generation equipment, gas streams to gas turbine systemsand air streams to various combustion furnaces, carry particulatecontaminant therein that should be filtered. Also, liquid streams andengine lube systems, hydraulic systems, coolant systems and fuelsystems, carry contaminant that should be filtered. It is preferred forsuch systems, that selected contaminant material been removed from (orhave its level reduced in) the fluid. A variety of fluid filter (air orliquid filter) arrangements have been developed for contaminantrejection. However, continued improvements are sought.

SUMMARY

According to the present disclosure, features useable in preferredfilter cartridges, such as air filter cartridges are provided. Thefeatures can be used together to provide a preferred filter cartridge,however some advantageous cartridges can be constructed to use onlyselected ones of the features. In addition, methods of construction anduse are provided.

A typical preferred filter cartridge according to the present disclosureincludes a coiled media combination and a cured-in-place jacket. Thecoiled media combination preferably comprises a coiled arrangement of afluted sheet secured to a facing sheet, most preferably with a facingsheet directed to the outside. The coiled media generally defines anouter side wall extending between first and second, opposite, flow endsof the coiled media combination.

The cured-in-place jacket preferably completely circumscribes and coversthe outer sidewall over an extension of at least 80% of a distance ofouter side wall extension between the first and second flow ends, morepreferably at least 95% of that distance and most preferably entirelyover that distance. The cured-in-place jacket preferably is configuredto seal an outer or tail end of the media combination.

In some instances, the filter cartridge includes a mold-in-place centerpiece or core. In some instances, when used, the mold-in-place centerpiece or core includes concave ends which each define a seal regionpositioned to seal a portion of an inner or lead end of the coiled mediacombination.

An example air filter cartridge utilizes both a cured-in-place jacketand a mold-in-place center piece or core.

The cured-in-place jacket preferably comprises a mold-in-place overmoldwhich includes, integrally therein, a housing seal arrangement. Atypical housing seal arrangement is an axial pinch seal.

Typically, polyurethane is a preferred material for the overmold, thehousing seal and the mold-in-place center core. Most preferably it is asa foamed polyurethane.

Mold arrangements and techniques for providing preferred assemblies areprovided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary, schematic, perspective view of z-filter mediauseable in arrangements according to the present disclosure.

FIG. 2 is a schematic, cross-sectional view of a portion of the mediadepicted in FIG. 1.

FIG. 3 is a schematic view of examples of various corrugated mediadefinitions.

FIG. 4 is a schematic view of a process for manufacturing mediaaccording to the present disclosure.

FIG. 5 is a cross-sectional view of an optional end dart for mediaflutes useable in arrangements according to the present disclosure.

FIG. 6 is a side, elevational view of a filter cartridge according tothe present disclosure.

FIG. 7 is a cross-sectional view of the element depicted in FIG. 6.

FIG. 8 is a schematic view of a mold arrangement having a media packtherein, for forming the filter cartridge of FIG. 6.

FIG. 9 is an enlarged, fragmentary view of a first portion of the moldarrangement of FIG. 8.

FIG. 10 is an enlarged, fragmentary view of the second portion of themold arrangement of FIG. 8.

FIG. 11 is a schematic side elevational view of a second filtercartridge according to the present disclosure.

FIG. 12 is a perspective view of the filter cartridge depicted in FIG.11.

FIG. 13 is a schematic view of a process of forming an alternate filtercartridge according to the present disclosure.

FIG. 14 is a schematic view of a second process for making an alternatefilter cartridge according to the present disclosure.

FIG. 15 is a perspective view of an obround filter cartridge havingfeatures according to the present disclosure.

FIG. 16 is a cross-sectional view taken along line 16-16, FIG. 15.

FIG. 17 is a cross-sectional view of a second obround cartridge.

FIG. 18 is a schematic cross-sectional view of a mold arrangement havinga media pack therein, for use in forming the arrangement of FIG. 17.

FIG. 19 is a cross-sectional view of the mold arrangement of FIG. 18,taken in the direction of arrow 19-19, thereof.

DETAILED DESCRIPTION I. Z-Filter Media Configurations, Generally

Fluted filter media can be used to provide fluid filter constructions ina variety of manners. One well known manner is as a z-filterconstruction. The term “z-filter construction” as used herein, is meantto refer to a filter construction in which individual ones ofcorrugated, folded or otherwise formed filter flutes are used to definesets of longitudinal, typically parallel, inlet and outlet filter flutesfor fluid flow through the media; the fluid flowing along the length ofthe flutes between opposite inlet and outlet flow ends (or flow faces)of the media. Some examples of z-filter media are provided in U.S. Pat.Nos. 5,820,646; 5,772,883; 5,902,364; 5,792,247; 5,895,574; 6,210,469;6,190,432; 6,350,296; 6,179,890; 6,235,195; Des. 399,944; Des. 428,128;Des. 396,098; Des. 398,046; and, Des. 437,401; each of these fifteencited references being incorporated herein by reference.

One type of z-filter media, utilizes two specific media componentsjoined together, to form the media construction. The two components are:(1) a fluted (typically corrugated) media sheet; and, (2) a facing mediasheet. The facing media sheet is typically non-corrugated, however itcan be corrugated, for example perpendicularly to the flute direction asdescribed in U.S. provisional 60/543,804, filed Feb. 11, 2004,incorporated herein by reference. Herein, the facing sheet may sometimesbe characterized as flat, if it is non-corrugated and non-fluted, evenwhen it is coiled in the filter media construction.

The fluted (typically corrugated) media sheet and the facing media sheettogether, are used to define media having parallel inlet and outletflutes. In some instances, the fluted sheet and non-fluted sheet aresecured together and are then coiled to form a z-filter mediaconstruction. Such arrangements are described, for example, in U.S. Pat.Nos. 6,235,195 and 6,179,890, each of which is incorporated herein byreference. In certain other arrangements, some non-coiled sections ofcorrugated media secured to flat media, are stacked on one another, tocreate a filter construction. An example of this is described in FIG. 11of U.S. Pat. No. 5,820,646, incorporated herein by reference.

For specific applications as described herein, coiled arrangements arepreferred.

Typically, coiling of the fluted sheet/facing sheet combination arounditself, to create a coiled media pack, is conducted with the facingsheet directed outwardly. Some techniques for coiling are described inU.S. provisional application 60/467,521, filed May 2, 2003 and PCTApplication US 04/07927, filed Mar. 17, 2004, each of which isincorporated herein by reference. The resulting coiled arrangementgenerally has, as the outer surface of the media pack, a portion of thefacing sheet, as a result.

The term “corrugated” used herein to refer to structure in media, ismeant to refer to a flute structure resulting from passing the mediabetween two corrugation rollers, i.e., into a nip or bite between tworollers, each of which has surface features appropriate to cause acorrugation affect in the resulting media. The term “corrugation” is notmeant to refer to flutes that are formed by techniques not involvingpassage of media into a bite between corrugation rollers. However, theterm “corrugated” is meant to apply even if the media is furthermodified or deformed after corrugation, for example by the foldingtechniques described in PCT WO 04/007054, published Jan. 22, 2004,incorporated herein by reference.

Corrugated media is a specific form of fluted media. Fluted media ismedia which has individual flutes (for example formed by corrugating orfolding) extending thereacross.

Serviceable filter element or filter cartridge configurations utilizingz-filter media are sometimes referred to as “straight through flowconfigurations” or by variants thereof. In general, in this context whatis meant is that the serviceable filter elements generally have an inletflow end (or face) and an opposite exit flow end (or face), with flowentering and exiting the filter cartridge in generally the same straightthrough direction. The term “serviceable” in this context is meant torefer to a media containing filter cartridge that is periodicallyremoved and replaced from a corresponding fluid cleaner. In someinstances, each of the inlet flow end and outlet flow end will begenerally flat or planar, with the two parallel to one another. However,variations from this, for example non-planar faces are possible.Examples of non-planar, opposite, flow faces are described below.

A straight through flow configuration (especially for a coiled mediapack) is, for example, in contrast to serviceable filter cartridges suchas cylindrical pleated filter cartridges of the type shown in U.S. Pat.No. 6,039,778, incorporated herein by reference, in which the flowgenerally makes a turn as its passes through the serviceable cartridge.That is, in a U.S. Pat. No. 6,039,778 filter, the flow enters thecylindrical filter cartridge through a cylindrical side, and then turnsto exit through an end face (in forward-flow systems). In a typicalreverse-flow system, the flow enters the serviceable cylindricalcartridge through an end face and then turns to exit through a side ofthe cylindrical filter cartridge. An example of such a reverse-flowsystem is shown in U.S. Pat. No. 5,613,992, incorporated by referenceherein.

The term “z-filter media construction” and variants thereof as usedherein, without more, is meant to refer to any or all of: a web ofcorrugated or otherwise fluted media secured to (facing) media withappropriate sealing to allow for definition of inlet and outlet flutes;or, such a media coiled or otherwise constructed or formed into a threedimensional network of inlet and outlet flutes; and/or, a filterconstruction including such media.

In FIG. 1, an example of media 1 useable in z-filter media is shown. Themedia 1 is formed from a corrugated sheet 3 and a facing sheet 4.

In general, the corrugated sheet 3, FIG. 1 is of a type generallycharacterized herein as having a regular, curved, wave pattern of flutesor corrugations 7. The term “wave pattern” in this context, is meant torefer to a flute or corrugated pattern of alternating troughs 7b andridges 7a. The term “regular” in this context is meant to refer to thefact that the pairs of troughs and ridges (7b, 7a) alternate withgenerally the same repeating corrugation (or flute) shape and size.(Also, typically in a regular configuration each trough 7b issubstantially an inverse of each ridge 7a.) The term “regular” is thusmeant to indicate that the corrugation (or flute) pattern comprisestroughs and ridges with each pair (comprising an adjacent trough andridge) repeating, without substantial modification in size and shape ofthe corrugations along at least 70% of the length of the flutes. Theterm “substantial” in this context, refers to a modification resultingfrom a change in the process or form used to create the corrugated orfluted sheet, as opposed to minor variations from the fact that themedia sheet 3 is flexible. With respect to the characterization of arepeating pattern, it is not meant that in any given filterconstruction, an equal number of ridges and troughs is necessarilypresent. The media 1 could be terminated, for example, between a paircomprising a ridge and a trough, or partially along a pair comprising aridge and a trough. (For example, in FIG. 1 the media 1 depicted infragmentary has eight complete ridges 7a and seven complete troughs 7b.)Also, the opposite flute ends (ends of the troughs and ridges) may varyfrom one another. Such variations in ends are disregarded in thesedefinitions, unless specifically stated. That is, variations in the endsof flutes are intended to be covered by the above definitions.

In the context of the characterization of a “curved” wave pattern ofcorrugations, the term “curved” is meant to refer to a corrugationpattern that is not the result of a folded or creased shape provided tothe media, but rather the apex 7a of each ridge and the bottom 7b ofeach trough is formed along a radiused curve. A typical radius for suchz-filter media would be at least 0.25 mm and typically would be not morethan 3 mm.

An additional characteristic of the particular regular, curved, wavepattern depicted in FIG. 1, for the corrugated sheet 3, is that atapproximately a midpoint 30 between each trough and each adjacent ridge,along most of the length of the flutes 7, is located a transition regionwhere the curvature inverts. For example, viewing back side or face 3a,FIG. 1, trough 7b is a concave region, and ridge 7a is a convex region.Of course when viewed toward front side or face 3b, trough 7b of side 3aforms a ridge; and, ridge 7a of face 3a, forms a trough. (In someinstances, region 30 can be a straight segment, instead of a point, withcurvature inverting at ends of the segment 30.)

A characteristic of the particular regular, curved, wave patterncorrugated sheet 3 shown in FIG. 1, is that the individual corrugationsare generally straight. By “straight” in this context, it is meant thatthrough at least 70%, typically at least 80% of the length between edges8 and 9, the ridges 7a and troughs 7b do not change substantially incross-section. The term “straight” in reference to corrugation patternshown in FIG. 1, in part distinguishes the pattern from the taperedflutes of corrugated media described in FIG. 1 of WO 97/40918 and PCTPublication WO 03/47722, published Jun. 12, 2003, incorporated herein byreference. The tapered flutes of FIG. 1 of WO 97/40918, for example,would be a curved wave pattern, but not a “regular” pattern, or apattern of straight flutes, as the terms are used herein.

Referring to the present FIG. 1 and as referenced above, the media 1 hasfirst and second opposite edges 8 and 9. When the media 1 is coiled andformed into a media pack, in general edge 9 will form an inlet end forthe media pack and edge 8 an outlet end, although an oppositeorientation is possible.

Adjacent edge 8 is provided a sealant bead 10, sealing the corrugatedsheet 3 and the facing sheet 4 together. Bead 10 will sometimes bereferred to as a “single facer” bead, since it is a bead between thecorrugated sheet 3 and facing sheet 4, which forms the single facer ormedia strip 1. Sealant bead 10 seals closed individual flutes 11adjacent edge 8, to passage of air therefrom.

Adjacent edge 9, is provided seal bead 14. Seal bead 14 generally closesflutes 15 to passage of unfiltered fluid therein, adjacent edge 9. Bead14 would typically be applied as the media 1 is coiled about itself,with the corrugated sheet 3 directed to the inside. Thus bead 14 willform a seal between a back side 17 of facing sheet 4, and side 18 of thecorrugated sheet 3. The bead 14 will sometimes be referred to as a“winding bead” since it is typically applied, as the strip 1 is coiledinto a coiled media pack. If the media 1 is cut in strips and stacked,instead of coiled, bead 14 would be a “stacking bead.”

Referring to FIG. 1, once the media 1 is incorporated into a media pack,for example by coiling or stacking, it can be operated as follows.First, air in the direction of arrows 12, would enter open flutes 11adjacent end 9. Due to the closure at end 8, by bead 10, the air wouldpass through the media shown by arrows 13. It could then exit the mediapack, by passage through open ends 15a of the flutes 15, adjacent end 8of the media pack. Of course operation could be conducted with air flowin the opposite direction.

For the particular arrangement shown herein in FIG. 1, the parallelcorrugations 7a, 7b are generally straight completely across the media,from edge 8 to edge 9. Straight flutes or corrugations can be deformedor folded at selected locations, especially at ends. Modifications atflute ends for closure are generally disregarded in the abovedefinitions of “regular,” “curved” and “wave pattern.”

Z-filter constructions which do not utilize straight, regular curvedwave pattern corrugation shapes are known. For example in Yamada et al.U.S. Pat. No. 5,562,825 corrugation patterns which utilize somewhatsemicircular (in cross section) inlet flutes adjacent narrow V-shaped(with curved sides) exit flutes are shown (see FIGS. 1 and 3, of U.S.Pat. No. 5,562,825). In Matsumoto, et al. U.S. Pat. No. 5,049,326circular (in cross-section) or tubular flutes defined by one sheethaving half tubes attached to another sheet having half tubes, with flatregions between the resulting parallel, straight, flutes are shown, seeFIG. 2 of Matsumoto '326. In Ishii, et al. U.S. Pat. No. 4,925,561(FIG. 1) flutes folded to have a rectangular cross section are shown, inwhich the flutes taper along their lengths. In WO 97/40918 (FIG. 1),flutes or parallel corrugations which have a curved, wave patterns (fromadjacent curved convex and concave troughs) but which taper along theirlengths (and thus are not straight) are shown. Also, in WO 97/40918flutes which have curved wave patterns, but with different sized ridgesand troughs, are shown.

In general, the filter media is a relatively flexible material,typically a non-woven fibrous material (of cellulose fibers, syntheticfibers or both) often including a resin therein, sometimes treated withadditional materials. Thus, it can be conformed or configured into thevarious corrugated patterns, without unacceptable media damage. Also, itcan be readily coiled or otherwise configured for use, again withoutunacceptable media damage. Of course, it must be of a nature such thatit will maintain the required corrugated configuration, during use.

In the corrugation process, an inelastic deformation is caused to themedia. This prevents the media from returning to its original shape.However, once the tension is released the flute or corrugations willtend to spring back, recovering only a portion of the stretch andbending that has occurred. The facing sheet is sometimes tacked to thefluted sheet, to inhibit this spring back in the corrugated sheet.

Also, typically, the media contains a resin. During the corrugationprocess, the media can be heated to above the glass transition point ofthe resin. When the resin then cools, it will help to maintain thefluted shapes.

The media of the corrugated sheet 3 facing sheet 4 or both, can beprovided with a fine fiber material on one or both sides thereof, forexample in accord with U.S. Pat. No. 6,673,136, incorporated herein byreference.

An issue with respect to z-filter constructions relates to closing ofthe individual flute ends. Typically a sealant or adhesive is provided,to accomplish the closure. As is apparent from the discussion above, intypical z-filter media, especially that which uses straight flutes asopposed to tapered flutes, large sealant surface areas (and volume) atboth the upstream end and the downstream end are needed. High qualityseals at these locations are critical to proper operation of the mediastructure that results. The high sealant volume and area, creates issueswith respect to this.

Attention is now directed to FIG. 2, in which a z-filter mediaconstruction 40 utilizing a regular, curved, wave pattern corrugatedsheet 43, and a non-corrugated flat sheet 44, is depicted. The distanceD1, between points 50 and 51, defines the extension of flat media 44 inregion 52 underneath a given corrugated flute 53. The length D2 of thearcuate media for the corrugated flute 53, over the same distance D1 isof course larger than D1, due to the shape of the corrugated flute 53.For a typical regular shaped media used in fluted filter applications,the linear length D2 of the media 53 between points 50 and 51 willgenerally be at least 1.2 times D1. Typically, D2 would be within arange of 1.2-2.0, inclusive. One particularly convenient arrangement forair filters has a configuration in which D2 is about 1.25-1.35×D1. Suchmedia has, for example, been used commercially in Donaldson Powercore™Z-filter arrangements. Herein the ratio D2/D1 will sometimes becharacterized as the flute/flat ratio or media draw for the corrugatedmedia.

In the corrugated cardboard industry, various standard flutes have beendefined. For example the standard E flute, standard X flute, standard Bflute, standard C flute and standard A flute. FIG. 3, attached, incombination with Table A below provides definitions of these flutes.

Donaldson Company, Inc., (DCI) the assignee of the present disclosure,has used variations of the standard A and standard B flutes, in avariety of z-filter arrangements. These flutes are also defined in TableA and FIG. 3.

TABLE A (Flute definitions for FIG. 3) DCI A Flute: Flute/flat = 1.52:1;The Radii (R) are as follows: R1000 = .0675 inch (1.715 mm); R1001 =.0581 inch (1.476 mm); R1002 = .0575 inch (1.461 mm); R1003 = .0681 inch(1.730 mm); DCI B Flute: Flute/flat = 1.32:1; The Radii (R) are asfollows: R1004 = .0600 inch (1.524 mm); R1005 = .0520 inch (1.321 mm);R1006 = .0500 inch (1.270 mm); R1007 = .0620 inch (1.575 mm); Std. EFlute: Flute/flat = 1.24:1; The Radii (R) are as follows: R1008 = .0200inch (.508 mm); R1009 = .0300 inch (.762 mm); R1010 = .0100 inch (.254mm); R1011 = .0400 inch (1.016 mm); Std. X Flute: Flute/flat = 1.29:1;The Radii (R) are as follows: R1012 = .0250 inch (.635 mm); R1013 =.0150 inch (.381 mm); Std. B Flute: Flute/flat = 1.29:1; The Radii (R)are as follows: R1014 = .0410 inch (1.041 mm); R1015 = .0310 inch (.7874mm); R1016 = .0310 inch (.7874 mm); Std. C Flute: Flute/flat = 1.46:1;The Radii (R) are as follows: R1017 = .0720 inch (1.829 mm); R1018 =.0620 inch (1.575 mm); Std. A Flute: Flute/flat = 1.53:1; The Radii (R)are as follows: R1019 = .0720 inch (1.829 mm); R1020 = .0620 inch (1.575mm).

Of course other, standard, flutes definitions from the corrugated boxindustry are known.

In general, standard flute configurations from the corrugated boxindustry can be used to define corrugation shapes or approximatecorrugation shapes for corrugated media. Comparisons above between theDCI A flute and DCI B flute, and the corrugation industry standard A andstandard B flutes, indicate some convenient variations.

II. Manufacture of Coiled Media Configurations Using Fluted Media,Generally A. Overview of Process; Option of Darting Flutes

In FIG. 4, one example of a manufacturing process for making a mediastrip corresponding to strip 1, FIG. 1 is shown. In general, facingsheet 64 and the fluted (corrugated) sheet 66 having flutes 68 arebrought together to form a media web 69, with an adhesive bead locatedtherebetween at 70. The adhesive bead 70 will form a single facer bead10, FIG. 1. An optional darting process occurs at station 71 to formcenter darted section 72 located mid-web. The z-filter media or Z-mediastrip 74 can be cut or slit at 75 along the bead 70 to create two pieces76, 77 of z-filter media 74, each of which has an edge with a strip ofsealant (single facer bead) extending between the corrugating and facingsheet. Of course, if the optional darting process is used, the edge witha strip of sealant (single facer bead) would also have a set of flutesdarted at this location.

Techniques for conducting a process as characterized with respect toFIG. 4 are described in PCT WO 04/007054, published Jan. 22, 2004incorporated herein by reference.

Still in reference to FIG. 4, before the z-filter media 74 is putthrough the darting station 71 and eventually slit at 75, it must beformed. In the schematic shown in FIG. 4, this is done by passing a flatsheet of media 92 through a pair of corrugation rollers 94, 95. In theschematic shown in FIG. 4, the flat sheet of media 92 is unrolled from aroll 96, wound around tension rollers 98, and then passed through a nipor bite 102 between the corrugation rollers 94, 95. The corrugationrollers 94, 95 have teeth 104 that will give the general desired shapeof the corrugations after the flat sheet 92 passes through the nip 102.After passing through the nip 102, the flat sheet 92 becomes corrugatedand is referenced at 66 as the corrugated sheet. The corrugated sheet 66is then secured to facing sheet 64. (The corrugation process may involveheating the media, in some instances.)

Still in reference to FIG. 4, the process also shows the facing sheet 64being routed to the darting process station 71. The facing sheet 64 isdepicted as being stored on a roll 106 and then directed to thecorrugated sheet 66 to form the Z-media 74. The corrugated sheet 66 andthe facing sheet 64 are secured together by adhesive or by other means(for example by sonic welding).

Referring to FIG. 4, an adhesive line 70 is shown used, to securecorrugated sheet 66 and facing sheet 64 together, as the sealant bead.Alternatively, the sealant bead for forming the facing bead could beapplied as shown as 70a. If the sealant is applied at 70a, it may bedesirable to put a gap in the corrugation roller 95, and possibly inboth corrugation rollers 94, 95, to accommodate the bead 70a.

The type of corrugation provided to the corrugated media is a matter ofchoice, and will be dictated by the corrugation or corrugation teeth ofthe corrugation rollers 94, 95. One preferred corrugation pattern willbe a regular curved wave pattern corrugation, of straight flutes, asdefined herein above. A typical regular curved wave pattern used, wouldbe one in which the distance D2, as defined above, in a corrugatedpattern is at least 1.2 times the distance D1 as defined above. In onepreferred application, typically D2=1.25−1.35×D1. In some instances thetechniques may be applied with curved wave patterns that are not“regular,” including, for example, ones that do not use straight flutes.

As described, the process shown in FIG. 4 can be used to create thecenter darted section 72. FIG. 5 shows, in cross-section, one of theflutes 68 after darting and slitting.

A fold arrangement 118 can be seen to form a darted flute 120 with fourcreases 121a, 121b, 121c, 121d. The fold arrangement 118 includes a flatfirst layer or portion 122 that is secured to the facing sheet 64. Asecond layer or portion 124 is shown pressed against the first layer orportion 122. The second layer or portion 124 is preferably formed fromfolding opposite outer ends 126, 127 of the first layer or portion 122.

Still referring to FIG. 5, two of the folds or creases 121a, 121b willgenerally be referred to herein as “upper, inwardly directed” folds orcreases. The term “upper” in this context is meant to indicate that thecreases lie on an upper portion of the entire fold 120, when the fold120 is viewed in the orientation of FIG. 5. The term “inwardly directed”is meant to refer to the fact that the fold line or crease line of eachcrease 121a, 121b, is directed toward the other.

In FIG. 5, creases 121c, 121d, will generally be referred to herein as“lower, outwardly directed” creases. The term “lower” in this contextrefers to the fact that the creases 121c, 121d are not located on thetop as are creases 121a, 121b, in the orientation of FIG. 5. The term“outwardly directed” is meant to indicate that the fold lines of thecreases 121c, 121d are directed away from one another.

The terms “upper” and “lower” as used in this context are meantspecifically to refer to the fold 120, when viewed from the orientationof FIG. 5. That is, they are not meant to be otherwise indicative ofdirection when the fold 120 is oriented in an actual product for use.

Based upon these characterizations and review of FIG. 5, it can be seenthat a preferred regular fold arrangement 118 according to FIG. 5 inthis disclosure is one which includes at least two “upper, inwardlydirected, creases.” These inwardly directed creases are unique and helpprovide an overall arrangement in which the folding does not cause asignificant encroachment on adjacent flutes.

A third layer or portion 128 can also be seen pressed against the secondlayer or portion 124. The third layer or portion 128 is formed byfolding from opposite inner ends 130, 131 of the third layer 128.

Another way of viewing the fold arrangement 118 is in reference to thegeometry of alternating ridges and troughs of the corrugated sheet 66.The first layer or portion 122 is formed from an inverted ridge. Thesecond layer or portion 124 corresponds to a double peak (afterinverting the ridge) that is folded toward, and in preferredarrangements, folded against the inverted ridge.

Techniques for providing the optional dart described in connection withFIG. 5, in a preferred manner, are described in PCT WO 04/007054,incorporated herein by reference. Techniques for coiling the media, withapplication of the winding bead, are described in PCT application US04/07927, filed Mar. 17, 2004, incorporated herein by reference.

Techniques described herein are particularly well adapted for use inmedia packs that result from coiling a single sheet comprising acorrugated sheet/facing sheet combination, i.e., a “single facer” strip.Certain of the techniques can be applied with arrangements that, insteadof being formed by coiling, are formed from a plurality of strips ofsingle facer.

Coiled media pack arrangements can be provided with a variety ofperipheral perimeter definitions. In this context the term “peripheral,perimeter definition” and variants thereof, is meant to refer to theoutside perimeter shape defined, looking at either the inlet end or theoutlet end of the media pack. Typical shapes are circular as describedin PCT WO 04/007054 and PCT application US 04/07927. Other useableshapes are obround, some examples of obround being oval shape. Ingeneral oval shapes have opposite curved ends attached by a pair ofopposite sides. In some oval shapes, the opposite sides are also curved.In other oval shapes, sometimes called racetrack shapes, the oppositesides are generally straight. Racetrack shapes are described for examplein PCT WO 04/007054 and PCT application US 04/07927.

Another way of describing the peripheral or perimeter shape is bydefining the perimeter resulting from taking a cross-section through themedia pack in a direction orthogonal to the winding access of the coil.

Opposite flow ends or flow faces of the media pack can be provided witha variety of different definitions. In many arrangements, such as thosedescribed in FIGS. 6 and 15 below, the ends are generally flat andperpendicular to one another. In other arrangements, described generallywith respect to FIGS. 11-14 below, the end faces include tapered,coiled, stepped portions which can either be defined to project axiallyoutwardly from an axial end of the side wall of the media pack; or, toproject axially inwardly from an end of the side wall of the media pack.These possibilities are described in more detail below.

The flute seals (single facer bead, winding bead or stacking bead) canbe formed from a variety of materials. In various ones of the cited andincorporated references, hot melt or polyurethane seals are described aspossible for various applications.

III. Formation of Seal Lead and Tail Ends; Generation of a PreferredMedia Pack Housing Seal Arrangement A. Background

The techniques described herein are typically used for provision of aserviceable air filter cartridge. The term “serviceable” in thiscontext, is meant to refer to an air filter cartridge which is used as areplacement part or service item in an air cleaner. The terms“replacement part,” “service item” and variants thereof are meant torefer to a filter cartridge which periodically is removed and replaced.

In general, preferred formation of a serviceable filter cartridge usingz-filter media in accord with the present disclosure involves:

1. Generating a coiled z-filter media strip in general accord with thetechniques described above in Sections I and II; and,

2. Incorporating the resulting media coil into a filter cartridgehaving: (a) a housing seal arrangement thereon; and (b) a lead end sealand a tail end seal for the media pack.

A housing seal is a seal incorporated into the resulting filtercartridge which is positioned to form a seal with an air cleanerhousing, when the filter cartridge is operably installed in the aircleaner for use. The term “housing seal” derives from the fact that theseal is between the filter cartridge and a housing component. The term“housing seal” is used to distinguish internal media pack seals (flutesseals) and other media seals (lead end and tail end seals, for example)within the media pack.

Flute seals have been previously discussed above in connection withFIGS. 1-5. In general flute seals are seals that either: close theoutlet flutes adjacent the inlet end or face of the media pack; or,close the inlet flutes adjacent the outlet end or face of the mediapack.

In general terms, a lead end seal for a media coil is a seal across alead end of the coiled strip of z-filter media, typically extendingparallel to the flutes. In this context, the term “lead end” is meant torefer to an end of the single facer or corrugated sheet/facing sheetcombination which begins the coil, and thus is located inside of thecenter of the resulting media coil after coiling. In typicalarrangements, two locations of seal at the lead end are potentiallyimportant namely: (1) a seal between the corrugated sheet and facingsheet of the single facer, across the lead end and parallel to theflutes; and, (2) sealing of the lead end of the single facer against anext outer layer, wrap or coil of the single facer as it is coiledaround, again across the lead end and parallel to the flutes.

Analogously, the tail end seal is a seal across the media strip (singlefacer), typically parallel to the flutes, at the tail or rear end of themedia strip (single facer) which is coiled. The tail end seal is at theoutside of the coil. Analogously to the lead end seal, the tail end sealhas two potentially important components namely: (i) a seal across thetail end between the facing sheet and the corrugating sheet of thecoiled single facer; and, (ii) a seal between the end of the singlefacer and the next inner layer, wrap or coil inside of the tail end.

In general terms, in preferred arrangements according to the presentdisclosure these seal features are accommodated in the following manner:

1. The lead end seal is formed by a process involving providing amold-in-place preferred center piece or core in the single facer coil;

2. The tail end seal is provided by applying a curable resin around themedia pack (i.e., circumscribing the media pack) to form acured-in-place coating to engulf the otherwise exposed facing sheet andtail end of the coiled strip; and

3. The housing seal is molded to the media pack and resin coating,preferably integral with the cured-in-place coating.

Herein when it is said that one component is integral with another,without more, it is meant that they are not separable from one anotherwithout destruction or damage. When it is said that they are moldedintegral, or integrally molded, it is meant they are molded together, atthe same time, from the same resin pool.

Preferably the housing seal and resin coat are molded together, as amold-in-place overmold directly applied around the media pack, asdescribed below. These features can be accommodated in arrangements ofvarious shapes, also as explained below.

B. An Example of Cylindrical Arrangement, FIGS. 6-10

In FIG. 6, a filter arrangement according to the present disclosure isdepicted. In FIG. 7 a cross-sectional view of the arrangement of FIG. 6is depicted. In FIG. 8 a cross-sectional view of a mold arrangementhaving a media pack therein useable to form the arrangement of FIG. 6 isdepicted. FIGS. 9 and 10 are enlargements of portions of FIG. 8.

Referring to FIG. 6, in general filter cartridge 201 is depicted. Thefilter cartridge 201 comprises a coiled media pack of z-filter media 202(FIG. 7) positioned with opposite flow surfaces 204 and 205, and with acured resin jacket 208 around the media pack 202 (FIG. 7) in extensionbetween the faces 204 and 205. Secured to an outer portion of the mediapack 202 is a housing seal arrangement 209.

Although alternatives are possible, for the particular arrangement 201shown, the cured resin jacket 208 and housing seal arrangement 209 arepreferably integral with one another, the two jointly forming overmold212. The overmold 212 is preferably molded-in-place from a polyurethanematerial suitable for forming the housing seal arrangement 209.Preferably a material which cures to an as-molded density of no greaterthan 30 lbs/cubic foot, typically no more than 25 lbs. per cubic foot,more preferably no greater than 22 lbs/cubic foot is used, althoughalternatives are possible, as discussed in section IV below. An exampleof a useable polyurethane material is described for example in U.S.application Ser. No. 10/112,097, filed Mar. 28, 2002, the completedisclosure of which is incorporated herein by reference. Althoughalternatives are possible, preferably the polyurethane overmold is curedto a hardness, Shore A, of no greater than 30, more preferably nogreater than 25, typically no greater than 20, for example 12-20.

Preferably the overmold 212 extends axially a distance of at least 80%of a length between the opposite flow faces 204 and 205. More preferablyit extends at least 90% of this distance, still more preferably at least95% and most preferably at least 98% up to 100% of this distance. Insome instances instead of providing a complete overmold, one can providea partial overmold which aligns with the portions of the winding beadand/or a single facer bead, to complete the sealing function.

In general, when applied as an overmold from a mold-in-place process,the overmold 212 seals the tail end seal 213, as discussed above, alongany portion of the tail end 213 that is underneath the overmold 212. Areason is that the tail end 213 of the coiled media strip becomesengulfed within the cured resin jacket 208, during the molding process.

Attention is now directed to FIG. 7, which depicts filter cartridge 201in cross-section. Referring to FIG. 7, the coiled media pack 202includes center 220. The center 220 needs to be sealed against air flowtherethrough. This is done by center piece or core 221. Core 221 alsoprovides for a lead end seal.

More specifically, the media lead end is shown in phantom at 222. Inparticular, for the arrangement shown, between regions 224 and 225, themold-in-place core 221 is provided in center 220. Thus, it seals atleast a portion of the lead end 222 of the media strip.

Still referring to FIG. 7, in general the preferred core 221 is a pouredand cured core. By this it is meant that the core 221 results frompouring a fluid resin into center 220 and allowing the resin to cure. Avariety of shapes and sizes for the core 221 are possible.

Typically when used as a lead end seal, the core 221 will be configuredto extend along, or engulf, at least 80% of the lead end seal length,typically at least 90% of that length. In some instances, for example inthe instance shown in FIG. 7, the core 221 may be configured to cover orenclose the entire lead end 22.

The core 221 can be configured with recesses as shown, or it can beconfigured to have no recesses or even to have one or more projectionsextending outwardly from the element.

When the core 221 is provided with recesses as shown, typically region224 will be spaced from end 204 at least 2 mm, and region 225 will bespaced from end 205 by at least 2 mm.

Region 227 extends from region 224 toward face 204, and terminates atface 204 as shown, or spaced therefrom within a preferred distance. Thisregion defines an outer seal wall 228 with a hollow center 229. The sealwall 228 continues the sealing of the lead end 222 of the media pack202. Region 227 can be viewed as a concave end 227a to core 221. Thehollow 229 is useable as described below. Herein, region 227 willsometimes be referred to as a concave end 227a with an axially outwardlyprojecting end skirt 228.

Skirt 228 is not required to terminate at end face 204, although suchtermination is shown in the preferred embodiment of FIG. 7. It canterminate short thereof and can still accomplish much of its function ofsealing the lead end 222, for example, by terminating at or adjacent thewinding bead seal or single facer seal in this region.

Analogously, between region 225 and surface 205, region 234 is provided,with outer seal area 235 and inner center recess 236. The seal area 235provides, among other things, for sealing of the lead end 222 of themedia 202 between region 225 and surface 205. The seal area 235 can beseen as a concave end 235a to core 221. Herein, region 225 willsometimes be referred to as a concave end 235a with an axially outwardlyprojecting end skirt 235. In some instances end skirt 235 is notrequired to terminate adjacent end face 205, as shown in the preferredembodiment of FIG. 7. Rather skirt 235 can terminate short of end face205, and still accomplish an appropriate seal of the lead end 222 atthis location, by terminating adjacent or in cooperation with a windingbead or seal bead at this location.

Still referring to FIG. 7, concave regions 227a and 235a are configuredfor receipt of housing componentry therein, when installed. Thiscomponentry can project into the element 201, into engagement withregions 235a and 227a, to support the cartridge 201 within the housing.In addition, concave regions 235a and 227a result from a preferredmolding approach as described below.

Still referring to FIG. 7, although not shown, structure could beembedded within core 221. For example a hollow core or other structurefrom a winding process could be left within region 220, to be engulfedwithin core 221 as a result of the molding operation.

Attention is now directed to FIG. 8, which shows a cross-sectional viewof a molding process to form filter cartridge 1. Referring to FIG. 8,mold arrangement 240 includes mold base 241 with center post 241a,slideable end pad 242 and cover 243, with center post 243a.

In operation, a media coil 202 is positioned in mold base 241 againstslideable end pad 242 with post 241a projecting into a center 202a ofcoil 202. Curable resin is then positioned within cavities 246, 247 andmold cover 243 is put in place, with post 243a projecting into center202a of coil 202. Although not required in all applications, the resin(typically a polyurethane) will typically be chosen to rise a selectedamount during cure, typically being chosen to increase by volume by atleast 20%, usually at least 40% and often a selected amount of greaterthan 50%. Indeed in some instances an increase in volume of 100% ormore, is conducted. There is no general requirement that the same resinbe used to form both the core and the overmold, although in someinstances the same resin could be used at both locations.

The post 241a is configured to form region 225 at seal area 235, whenresin is positioned in region 241, before mold cover 243 is put inplace. Mold cover 243 includes projection 243a which forms region 224and seal region 228, FIG. 7, when the resin in region 250 rises andcures. Typically resin for cure will be dispensed in region 241, then,before mold cover 243 is put in place. The resin, of course, will seallead end 202b after cure.

As configured, post 243a engages media coil 202, to inhibit undesirablelevels of resin flash from extending over surface 204, FIG. 7, duringcure. Similarly post 241a in cooperation with engagement of media coil202 inhibits undesirable levels of resin flash extending over surface205, FIG. 7, during cure.

The coil 245 will be positioned in mold arrangement 250 with the windingbead positioned either adjacent cover 243 or base 241. The choice willdepend on specific features of the mold, and which end of the finalproduct is selected for the seal bead.

Of course resin positioned in cavity 246 will form overmold 208 andhousing seal portion 209, FIGS. 6 and 7.

Slideable end pad 242, FIG. 8, facilitates demolding. In particular,pocket 255 circumscribes post 241a underneath a portion of pad 242 at aregion adjacent base outer wall 256. The mold arrangement 240 willtypically be constructed such that compressed air can be selectivelydriven into pocket 255, once mold cover 243 is removed, to driveslideable base 241 in the direction of arrows 257, pushing the resultingmolded cartridge (cartridge 201, FIG. 6) out of the mold arrangement240.

Attention is now directed to FIG. 9, which shows an enlarged view of aportion of FIG. 8. In FIG. 9, an interface between mold base 241,slideable end pad 242 and media coil 202, adjacent base outer wall 256is shown. For the particular arrangement shown, slideable end pad 242includes circumferential projection 261 which tapers to a thin edge inextension from surface 262 around media coil 202. Pushing the media coil202 into circumferential projection 261, will help ensure that resindoes not undesirably flash across end face 264, during molding. It alsowill facilitate demolding. Projection 261 can be configured to preventresin from engaging the media coil 202 at region 202c. However intypical applications, a small amount of resin flash will be able tocreep over media 202 at region 202c, i.e., the pressing will not be sotight as to prevent this.

Referring to FIG. 8, adjacent surface 267 of mold cover 243 a similartapered area 268 is provided, to inhibit flash across surface 269 duringmolding. Again, although pinching at region 268 can be conducted such asto prevent resin from extending all the way to adjacent surface 269,preferably the pinching is not so tight as to prevent resin extensionfrom this location. A very small amount creep across to the surface 269,typically less than 5 mm, is acceptable. The same is true adjacent end205.

Typically before the coil 202 is positioned within mold arrangement 240,the tail end of the coil 202 is taped or tacked down, so that it doesnot uncoil or open when positioned in the mold. In addition, oralternatively, pinching of the coil 202 at regions 261, 268, FIG. 8,will also tend to inhibit uncoiling.

In FIG. 10, there are shown, in enlarged view, portions of the moldarrangement 240 which form the housing seal arrangement 209, FIG. 7, ofthe resulting filter cartridge 201.

Referring to FIG. 7, the housing seal arrangement 209 has oppositegenerally axially directed surfaces 270, 271 separated by centralperipheral region 272. In operation, housing seal 209 will be compressedbetween a first housing component directed into housing portion engagingsurface 270 and an opposite housing portion engaging surface 271, underaxial compression. In this context the term “axial” is generally meantto refer to forces in the direction of a longitudinal axis of thecartridge 201, or alternately stated in a direction generallycorresponding to a line drawn between faces 204, 205. Such seals aregenerally referred to herein as “axial seals.”

It is noted that surfaces 270 and 271 are each contoured, and are notflat and parallel to one another, in the preferred arrangement. Sealswhich have generally flat surfaces at these locations are possible,including ones where the surfaces are flat and parallel to one another.

Attention is now directed to FIG. 10, which shows the mold arrangementfor forming housing seal 209.

Referring to FIG. 10, the break line between mold parts 241, 243 isshown at 280. It is noted that the break line is configured to engage ina central portion of surface 281 of a mold cavity. Surface 281 is thesurface which will form peripheral region 272 of the housing sealarrangement 209, FIG. 7. Thus the mold line or mold break line does notengage either of the sealing surfaces 270 or 271, in the preferredembodiment.

Referring again to FIG. 10, at 285, the mold surface which will formseal surface 270, FIG. 7 is indicated. Surface 285 has several featuresof interest, in the preferred embodiment shown. First, surface 285extends generally at an angle relative to surface 286 of the media pack202) that is non-perpendicular to the surface 286, and generally is atan angle A, FIG. 10, within the range of 30°-70°, typically 40°-60°,preferably 45°-55°. Such a general angle helps ensure that as the resinmaterial rises within the cavity 246, air bubbles will not form alongsurface 285, negatively affecting the mold in surface 270, FIG. 7.

In addition, surface 285 is not a straight surface, but is somewhatcontoured as shown in FIG. 10, to result in a contoured surface 270,FIG. 7. A contouring can be used to provide for preferred engagementwith a housing part.

Referring to FIG. 10, mold region 288 is configured to form seal surface271, FIG. 7. At region 288 the mold surfaces closer to perpendicular tomedia surface 286. Specifically the example shown as an angle B of about70°, with typical arrangements being 60°-85°, of course a perpendiculararrangement, with angle B being 90°, is possible.

Referring to FIG. 7, the resulting surface 271 has a shape or contourselected to be appropriate for engaging a housing component.

Still referring to FIG. 7, it is noted that cartridge 201 wouldtypically be installed with surface 204 upstream and surface 205downstream, although alternate mounting is possible.

Typically region 272 of housing seal 209 is positioned at a locationoutwardly (radially) from media pack 202 (before any compression ordistortion) a distance of at least 5 mm, typically at least 10 mm.Typically an axial extension of surface 272, spacing surfaces 270, 271,is at least 4 mm, typically at least 6 mm (before any compression ordistortion).

Referring to FIG. 7, typically point 270a, corresponding to a junctionbetween surface 270 and a remaining of portion of overmold 208 is spacedfrom surface 204 a distance of at least 3 mm, typically at least 5 mm.Similarly point 271a, located at junction between surface 271 and aremainder of overmold 208 is spaced from surface 205 a distance of atleast 3 mm, typically at least 5 mm. In usual examples, juncture 271a isspaced from surface 205 by a substantial distance corresponding at least40% of an axial length of the cartridge 201.

Also referring to FIG. 7, it is noted that because the seal arrangement209 is positioned spaced from both ends 204 and 205, two region 280, 281of overmold are provided. Region 280 generally tapers downwardly inthickness, in extension from housing seal 209 toward end surface 205.The angle of inward taper is generally nor more than 10°, typically nomore than 5°.

At region 281, the overmold extends downwardly at an angle andthickness, between housing seal 209 toward end surface 204. The angle oftapering is generally no more than 10°, typically no more than 5°.

It is not required that seal 209 be spaced both end surfaces 204, 205,this is a matter of choice for the particular arrangement constructed.However when housing seal 209 is spaced from both surface 204, 205, theextent of spacing is typically at least 10 mm and preferably at least 15mm from each. Again, in some embodiments the housing seal 209 can bepositioned flush with, or very close to, one of the end surfaces 204,205.

It is noted that the identified overmold could be used in filtercartridge arrangements in which the central volume 220 and the lead endare sealed differently from the way shown in FIG. 7.

C. Bullet Nosed or Conical Version FIGS. 11-14

Attention is now directed to FIGS. 11 and 12 in which filter cartridge300 is schematically depicted. Referring to FIG. 11, the cartridge 300includes an overmold 301 and a media pack 302. The overmold 301comprises side wall section 303 and housing seal 304. In a typicalarrangement the housing 304 would be integral with a side wall 303, bothbeing formed in a single mold-in-place operation analogous to the onedescribed above with respect to FIGS. 6-10.

The media pack 302 comprises a coiled single facer arrangementconfigured to have one axially outwardly projecting end or flow surface306 and one inwardly axially projecting end or flow surface 307.Referring to FIG. 11, surface 306 includes central planar portion 308and outer sloped portion or surface (skirt) 309. It is noted that in atypical arrangement sloped surface (skirt) 309 would not be a perfectstraight line, but would rather comprise a series of coiled stepsresulting from coiled layers of media single facer. Typically face 307would have an analogous surface with central portion 314 and outerangular skirt 315.

In typical arrangements the center portion 306 will comprise at least20%, for example 20 to 60% inclusive; typically 30-50%, inclusive, ofthe total distance across the cartridge 300 between regions 320, 321;the distance between regions 320 and 321 being a largest axialcross-section corresponding to a diameter of the media pack, for a mediapack having a circular outer periphery.

The same would be true for center section 314. That is, center section314 preferably extends at least 20%, for example 20%-60%, inclusivetypically 30-50%, inclusive of the total distance of a largest axialcross-section of the cartridge 300 between regions 320, 321; thedistance between regions 320 and 321 being a largest axialcross-sectional corresponding to a diameter of the media pack, for amedia pack having a circular outer periphery.

Angles D, FIG. 11, generally define a “skirt angle” for regions 309,315. These angles D indicate the extent to which regions 309 and 315 areconical. Typically angle D will be at least 5° and not more than 40°,typically 10-30°, often 15-25°.

In general, the configuration of the media pack 302 results from pushingsurface 307 in the direction of arrow 330 an appropriate amount, priorto molding overmold 301.

It is noted that the media pack 306 would typically require a centerseal and lead end seal. A core analogous to the core 221 described abovewith respect to cartridge 201, FIG. 7 could be used, althoughalternatives are possible.

In FIG. 11, a tail end 306a of the media pack 306 is shown engulfed inthe overmold 301.

For the particular arrangement shown in FIG. 11, the housing seal 304 islocated adjacent surface 306 as opposed to spaced therefrom as shown forthe arrangement of FIG. 6. An alternative in which the housing seal 304is molded at a location spaced from surface 306 is, of course, possible.

In FIG. 12, element 300 is shown in perspective view and thus core 330is viewable.

Of course as with FIGS. 6 and 7, FIGS. 11 and 12 are partiallyschematic, and thus individual coils of the media are not specificallydepicted.

Attention is directed to FIG. 13, which shows a general process forforming a conical or bullet nosed media pack having an overmold.Referring to FIG. 13 at 350 a mold arrangement comprising side wall 351,cover 352, base 353 and center piece 354 is depicted. Base 353 defines aslanted upper surface 353a.

At 360, mold 350 is shown having media pack 361 positioned therein. Themedia pack 361 would generally comprise a coiled media pack arrangement.Because it is pushed on base 353, it has adopted the conical (bulletnosed) arrangement or configuration. At 370, the mold 350 is shownclosed, with resin therein to form overmold 371 around media pack 361.The resin is shown forming an overmold 372 with a housing seal 373secured thereto.

At 380, the completed element 381 is shown. It is noted that core 390was also formed during the molding at 370.

From FIG. 13, it can be understood that a variety of different shapedarrangements can be made, using the principles. Different configurationsand different over molds are possible, by modification of thetechniques.

One modification is depicted in FIG. 14. At 400 a mold arrangement isshown, comprising cover 401 and base 402. They are shown openable, forpositioning in media pack therein. At 420, the mold 400 is shown with amedia pack 421 therein, and resin positioned to provide overmold 425 andcentral core 426. The overmold 425 includes housing seal 428, in thisinstance positioned between end surfaces 430, 431, and spaced from each.

D. Obround Versions FIGS. 15-19

Referring to FIG. 15, an obround filter cartridge 500 is depicted. Thecartridge 500 comprises a media pack 501 and an overmold 502. Theovermold 502 includes side wall portions 503, 504 and housing seal 505.Preferably the portions 503, 504, 505 comprise an integrally moldedovermold 502, which seals tail end 501b of media pack 501. Cartridge 501includes center core 510. Preferably the center core 510 is moldedanalogously to core 221, FIG. 7.

In general the media pack 501 has a generally oval perimeter shape, withopposite curved ends 520, 521 and opposite sides 522, 523. For theparticular arrangement shown, the shape is racetrack with centerportions of sides 522 and 523 being straight and parallel to oneanother. Of course curved sides can be used.

In FIG. 16 a cross-sectional view of element 500 is depicted. In FIG. 16one can see opposite flow surfaces 530, 531 of the media pack 501.

For the arrangement shown in FIG. 16, the surfaces 530 and 531 areplanar and parallel to one another. Conical or bullet nosed steppedsurfaces analogous to those for a circular element shown in FIGS. 11 and12, can be provided, in an analogous manner.

Referring to FIG. 16, section 503 is generally analogous to section 280,FIG. 7, and tapers from housing seal 505 toward end 531; and, region 504is generally analogous to region 281, and tapers from housing seal 505toward end surface 530. Of course alternative configurations arepossible.

Referring to FIG. 16, core 510 include axial, oppositely, outwardlyprojecting skirts 510a and 510b on opposite sides of the portion 510c.Alternate configurations for core 510 are possible. Core 510 of courseseals lead end 501a, media pack 501.

In FIG. 17, an analogous obround element 600 is shown in cross-section,comprising media pack 601 and overmold 602. The overmold 602 comprisesseal portion 605 and end portions 606, 607. The particular sealarrangement 605 depicted in FIG. 17 is also an axial seal arrangement,but has a different configuration than arrangement 505, FIG. 16.

Center core 610 is shown comprising central portion 611 and oppositelydirected concave end portions 612, 613, comprising axially outwardlydirected skirts. Region 612 comprises central recess 614 and axiallyprojecting edge regions 615. Region 613 generally analogously comprisescentral portion 618 and axially projecting end regions 619. In general,core 610 seals lead end 601a of media pack 601.

In FIG. 17, section 607 is generally analogous to section 280, FIG. 7,and tapers in extension from housing seal 605 toward end surface 620 ofmedia pack 601; and, region 606 is generally analogous to region 281 andtapers downwardly in thickness from housing seal 605 toward end flowsurface 621 of media pack 601. Of course alternatives are possible.

In FIG. 18, cross-sectional view of a mold arrangement 640 useable toform element 600 is shown. The mold arrangement 640 is depicted withmedia pack 601 positioned therein. The mold arrangement 640 comprisesbase 645, cover 646 and moveable platform 647, analogously to moldarrangement 240, FIG. 8. When cavities 650 and 651 are provided withresin, after molding an arrangement analogous to that shown in FIG. 17will result.

In FIG. 19 the same mold arrangement 640 is depicted in cross-sectionalview taken perpendicularly to the view of FIG. 18. Note projections 660,661, which will form regions 614 and 613, respectively, in the cartridge600, FIG. 17.

It is noted that for the obround version shown in cross-section in FIGS.16 and 17, cores 510, 610 are provided. Alternately, obround versionscan be provided without center cores, but rather the sealing provided bycompressing the media such that the winding bead provides a seal at oneend. This approach is described for example in PCT application numberUS04/07927, filed Mar. 17, 2004, incorporated herein by reference.Further when such an approach is used, typically a lead end seal needsto be provided in the single facer strip, between the corrugated sheetand the facing sheet. If such a seal is required, it can be provided bysealant applied at this location or by other means, prior to coiling.

IV. Some Final Observations

It is noted that surfaces within the molds, especially side surfaces,can be configured to have trademarks, decorations or other indicia inthe overmolds. The indicia is a matter of choice and it can includetrademark information, design presentation or instructional orinformational material.

Herein the cured-in-place jackets are shown provided as mold-in-placejackets or overmolds with integral housing seal arrangements. They canbe provided separately, for example with a jacket first applied and ahousing seal later applied. The jacket does not need to be applied bymolding, for example it could be sprayed or otherwise applied, with afollow-up cure. The housing seal is preferably molded in place. However,it can be separately molded and attached in some applications.

The housing seals depicted in here are generally axial seals, that isthey operate for axial compression between housing components.Alternatively, radial seals could be molded in the same locations, insome arrangements, if desired. Also, multiple seals could be used.

The arrangements shown have preferred cores with concave ends. Again,alternate cores are possible, in some applications.

Herein, three regions preferably of molded urethane (not counting fluteseals if urethane is used at that location) are generally described.These three regions are: the housing seal; the overmold; and, if used,the mold-in-place core. It is not required that the same urethane wouldbe used at all three locations, although in some instances the sameurethane may be.

With respect to the core, urethane having a density of no more than 15lbs./cubic foot (0.24 g/cc), and sometimes no more than 10 lbs./cubicfoot (0.16 g/cc), can be used, although alternatives (higher density)are possible. It is anticipated that the density would typically be atleast 5 lbs/cubic foot (0.08 g/cc).

With respect to the parts of the overmold that are not a housing seal, asimilar requirement is made.

As to the part of the overmold that forms the housing seal, typically amaterial having a density of at least 10 lbs./cubic foot (0.16 g/cc)would be preferred, although material as low as 5 lbs./cubic foot (0.08g/cc) may be acceptable for some light duty applications. In manyinstances it may be preferred to have a material having a density nogreater than about 22 lbs./cubic foot (0.35 g/cc).

With respect to all three locations, the upper range possible is amatter of choice. For example the core can be poured from a materialthat will cure to a relatively high density, if desired. Thus a materialhaving a density of 50 lbs./cubic foot (0.8 g/cc) or more could be used.Such a material would typically have a hardness Shore A of 80 orgreater. However such a material will not typically be advantageous,since it adds weight and cost.

As to the overmold and housing seal, again a relatively firm or hardmaterial can be used in some instances. However in many instances thehousing configuration will be such as to take, by preference, arelatively soft housing seal as characterized.

What is claimed is:
 1. An air filter cartridge comprising: (a) a coiledmedia combination comprising a fluted sheet secured to a facing sheetand defining a set of inlet flutes and a set of outlet flutes extendingbetween first and second, opposite, media combination flow ends; thecoiled media combination defining: (i) a coil having a center extendingbetween the first and second, opposite, media combination flow ends andan outer sidewall extending between the first and second, opposite,media combination flow ends; and, (ii) a media combination lead endpositioned inside of the coil center; and, (b) a mold-in-place centerresulting from putting a sealant material into an open end of the centerof the coil and allowing the sealant to seal at least a portion of thelead end and to close the center against air flow therethrough.
 2. Anair filter cartridge according to claim 1 wherein: (a) the mold-in-placecenter has opposite ends at least one of which has an axially,outwardly, projecting end skirt to seal a portion of the lead end.
 3. Anair filter cartridge according to claim 1 wherein: (a) the mold-in-placecenter is formed from a resin that increases in volume by at least 20%during cure.
 4. An air filter cartridge according to claim 1 wherein:(a) the mold-in-place center is formed from a resin that increases involume by at least 40% during cure.
 5. An air filter cartridge accordingto claim 1 wherein: (a) the mold-in-place center is formed from a resinthat increases in volume by at least 50% during cure.
 6. An air filtercartridge according to claim 1 wherein: (a) the mold-in-place centercomprises a foamed polyurethane core formed from a resin that increasesin volume by at least 20% during core.
 7. An air filter cartridgeaccording to claim 1 wherein: (a) the center has a density of no greaterthan 0.24 g/cc.
 8. An air filter cartridge according to claim 1 wherein:(a) the coiled media combination has a circular perimeter shape.
 9. Anair filter cartridge according to claim 1 wherein: (a) a housing sealarrangement is positioned secured to the media pack combination.
 10. Anair filter cartridge according to claim 9 wherein: (a) the housing sealarrangement extends around the media pack combination.
 11. An air filtercartridge according to claim 10 wherein: (a) the housing sealarrangement comprises a mold-in-place seal positioned on an outside ofthe media pack combination.
 12. An air filter cartridge according toclaim 11 wherein: (a) the housing seal arrangement comprises an axialpinch seal.
 13. An air filter cartridge according to claim 9 wherein:(a) the housing seal arrangement includes a mold-in-place seal member.14. An air filter cartridge according to claim 9 wherein: (a) thehousing seal arrangement comprises an axial pinch seal.
 15. An airfilter cartridge according to claim 14 wherein: (a) the axial pinch sealhas opposite housing engagement surfaces spaced at least 4 mm apart. 16.A method of forming an air filter cartridge; the method comprising: (a)coiling a strip of fluted media secured to facing media to define amedia combination comprising: (i) inlet and outlet flutes; (ii) a coilcenter; and, (iii) a media combination lead end positioned in the coilcenter; and, (b) molding a molded-in-place center within an end of thecoil center; (i) the step of molding comprising putting a sealantmaterial in an end of the coil center, after the step of coiling, andmolding the sealant material to seal at least a portion of a lead endand to seal the center against air flow therethrough.
 17. A methodaccording to claim 16 wherein: (a) the step of molding comprises using aresin that increases in volume by at least 40% during cure.
 18. A methodaccording to claim 16 wherein: (a) the step of molding comprises using aresin that increases in volume by at least 50% during cure.
 19. A methodaccording to claim 16 wherein: (a) the step of molding comprises curinga polyurethane resin.
 20. An air filter cartridge according to claim 16wherein: (a) the fluted sheet is connected to the facing sheet withsonic welding.
 21. An air filter cartridge according to claim 1 wherein:(a) the coiled media includes sonically welded media therein.
 22. An airfilter cartridge according to claim 1 wherein: (a) the mold-in-placecenter comprises a mold-in-place center core is configured to extendalong at least 80% of a lead end seal length.
 23. An air filtercartridge according to claim 1 wherein: (a) the mold-in-place center isformed from a resin that will rise during cure.
 24. A method accordingto claim 16 wherein: (a) the step of molding includes projecting aprojection on a mold into the coil center.
 25. A method according toclaim 16 wherein: (a) the mold-in-place center is formed from a resinthat will rise during cure.
 26. A method according to claim 16 wherein:(a) the mold-in-place center is formed from a resin that will increasein volume by at least 40% during cure.
 27. An air filter cartridgecomprising: (a) a coiled media combination comprising a fluted sheetsecured to a facing sheet and defining a set of inlet flutes and a setof outlet flutes and defining first and second, opposite, mediacombination flow ends; the coiled media combination defining a coilhaving a center extending between the first and second, opposite, mediacombination flow ends and an outer sidewall extending between the firstand second, opposite, media combination flow ends; and, (b) amold-in-place center resulting from putting at least a portion ofsealant material through an open end of the center of the coil andallowing the sealant to seal and close the center against air flowtherethrough.
 28. An air filter cartridge according to claim 27 wherein:(a) the mold-in-place center is formed from a resin that increases involume by at least 20% during cure.
 29. A method of forming an airfilter cartridge; the method comprising: (a) coiling a strip of flutedmedia secured to facing media to define a media combination comprising:(i) inlet and outlet flutes; and (ii) a coil center; and (b) molding amolded-in-place center within an end of the coil center; (i) the step ofmolding being conducted after the step of coiling and comprising puttingat least a portion of sealant material through an open end of the coilcenter and molding the sealant material to seal the center against airflow therethrough.
 30. A method according to claim 29 wherein: (a) thestep of molding comprises using a resin that increases in volume by atleast 40% during cure.
 31. An air filter cartridge comprising: (a) acoiled media combination comprising fluted media secured to facing mediaand defining a media combination inlet flow end and an opposite mediacombination outlet flow end; the media combination defining: (i) a coilhaving a center extending between the opposite flow ends; (ii) a mediacombination lead end positioned inside of the coil center; and, (b) amold-in-place center resulting from putting a sealant material into anopen end of the center of the coil and allowing the sealant to seal atleast a portion of the lead end and to close the center against air flowtherethrough.
 32. An air filter cartridge according to claim 31 wherein:(a) the mold-in-place center is formed from a resin that increases involume by at least 20% during cure.
 33. An air filter cartridgeaccording to claim 32 wherein: (a) a housing seal arrangement ispositioned secured to the media pack combination.
 34. A method ofmanufacturing an air filter cartridge comprising steps of: (a) applyinga curable resin circumscribing a filter media pack, wherein the filtermedia pack comprises a combination of a fluted sheet and a facing sheethaving an inlet flow face and an outlet flow face, and defining aplurality of flutes extending from the inlet flow face to the outletflow face, wherein the step of applying a curable resin circumscribing afilter media pack provides the curable resin around a perimeter of themedia pack between the inlet flow face and the outlet flow face; (b)curing the curable resin to form a cured-in-place coating circumscribingthe filter media pack to provide the cured-in-place coating extending atleast 80% of a length between the filter media pack inlet flow face andfilter media pack the outlet flow face; and (c) providing the air filtercartridge with a molded housing seal around the media pack, wherein thestep of providing the air filter cartridge with a molded housing sealaround the filter media pack is separate from the step of applying acurable resin circumscribing the filter media pack.
 35. A methodaccording to claim 34 wherein: (a) the steps of applying and curingresults in the cured-in-place coating extending at least 90% of thelength between the filter media pack inlet flow face and the filtermedia pack outlet flow face.
 36. A method according to claim 34 wherein:(a) the steps of applying and curing results in the cured-in-placecoating extending at least 95% of the length between the filter mediapack inlet flow face and the filter media pack outlet flow face.
 37. Amethod according to claim 34 wherein: (a) the steps of applying andcuring results in the cured-in-place coating extending at least 98% upto 100% of the length between the filter media pack inlet flow face andthe filter media pack outlet flow face.
 38. A method according to claim34 wherein: (a) the step of applying a curable resin comprises sprayingthe curable resin.
 39. A method according to claim 34 wherein: (a) thestep of providing the air filter cartridge with a molded housing sealcomprises molding the housing seal directly to the filter media pack.40. A method according to claim 34 wherein: (a) the step of applying thecurable resin comprises molding the curable resin in place.
 41. A methodaccording to claim 34 wherein: (a) the step of providing the air filtercartridge with a molded housing seal comprises molding the housing sealover the cured-in-place coating.
 42. A method according to claim 34wherein: (a) the step of providing the air filter cartridge with amolded housing seal comprises attaching a separately molded housingseal.
 43. A method according to claim 34 wherein: (a) the combination ofthe fluted sheet and the facing sheet comprises a lead end and a tailend, and the tail end is sealed by the cured-in-place coating.
 44. Amethod according to claim 34 wherein: (a) the inlet flow face and theoutlet flow face have generally flat surfaces.
 45. A method according toclaim 44 wherein: (a) the inlet flow face and the outlet flow face areparallel.
 46. A method according to claim 34 wherein: (a) the housingseal includes opposite axially directed surfaces separated by aperipheral surface.
 47. A method according to claim 46 wherein: (a) theopposite axially directed surfaces of the housing seal are flatsurfaces.
 48. A method according to claim 47 wherein: (a) the oppositeaxially directed surfaces of the housing seal are parallel.
 49. A methodaccording to claim 34 wherein: (a) the filter media pack comprises thefluted sheet and the facing sheet in a coiled arrangement.
 50. A methodaccording to claim 49 further comprising: (a) molding a molded-in-placecenter within the coiled arrangement.
 51. A method according to claim 49wherein: (a) the coiled arrangement has a circular perimeter shape. 52.A method according to claim 49 wherein: (a) the coiled arrangement has aperimeter shape with opposite curved ends and opposite sides.
 53. Amethod according to claim 52 wherein: (a) the opposite sides arestraight and parallel.
 54. A method of manufacturing an air filtercartridge comprising steps of: (a) spraying a curable resin around aperiphery of a filter media pack and forming a cured-in-place coatingaround the filter media pack, wherein the filter media pack comprises acombination of a fluted sheet and a facing sheet having an inlet flowface and an outlet flow face, and defining a plurality of flutesextending from the inlet flow face to the outlet flow face, wherein thestep of spraying a curable resin around a periphery of a filter mediapack provides spraying the curable resin around a perimeter of the mediapack between the inlet flow face and the outlet flow face; and (b)providing the air filter cartridge with a molded housing seal around thefilter media pack.
 55. A method according to claim 54 wherein: (a) thesteps of spraying and curing comprises forming the cured-in-placecoating extending at least 80% of the length between the filter mediapack inlet flow face and the filter media pack outlet flow face.
 56. Amethod according to claim 54 wherein: (a) the steps of spraying andcuring comprises forming the cured-in-place coating extending at least90% of the length between the filter media pack inlet flow face and thefilter media pack outlet flow face.
 57. A method according to claim 54wherein: (a) the steps of spraying and curing comprises forming thecured-in-place coating extending at least 95% of the length between thefilter media pack inlet flow face and the filter media pack outlet flowface.
 58. A method according to claim 54 wherein: (a) the cured-in-placecoating extending at least 98% up to 100% of the length between thefilter media pack inlet flow face and the filter media pack outlet flowface.
 59. A method according to claim 54 wherein: (a) the step ofproviding the air filter cartridge with a molded housing seal comprisesmolding the housing seal directly to the filter media pack.
 60. A methodaccording to claim 54 wherein: (a) the step of providing the air filtercartridge with a molded housing seal comprises molding the housing sealover the cured-in-place coating.
 61. A method according to claim 54wherein: (a) the step of providing the air filter cartridge with amolded housing seal comprises attaching a separating molded housingseal.
 62. A method according to claim 54 wherein: (a) the inlet flowface and the outlet flow face have generally flat surfaces.
 63. A methodaccording to claim 62 wherein: (a) the inlet flow face and the outletflow face are parallel.
 64. A method according to claim 54 wherein: (a)the combination of the fluted sheet and the facing sheet comprises alead end and a tail end, and the tail end is sealed by thecured-in-place coating.
 65. A method according to claim 54 wherein: (a)the filter media pack comprises the fluted sheet and the facing sheet ina coiled arrangement.
 66. A method according to claim 65 furthercomprising: (a) molding a molded-in-place center within the coiledarrangement.
 67. A method according to claim 65 wherein: (a) the coiledarrangement has a circular perimeter shape.
 68. A method according toclaim 65 wherein: a) the coiled arrangement has a perimeter shape withopposite curved ends and opposite sides.
 69. A method according to claim68 wherein: (a) the opposite straight sides are straight and parallel.70. A method according to claim 54 wherein: (a) the housing sealincludes opposite axially directed surfaces separated by a peripheralsurface.
 71. A method according to claim 70 wherein: (a) the oppositeaxially directed surfaces of the housing seal are flat and parallelsurfaces.
 72. An air filter cartridge comprising: (a) a filter mediapack comprising a fluted sheet and a facing sheet having an inlet flowface and an outlet flow face; and defining a plurality of flutesextending from the inlet flow face to the outlet flow face; (b) acured-in-place resin jacket provided around a periphery of the filtermedia pack between the filter media pack inlet flow face and the filtermedia pack outlet flow face and extending at least 80% of a lengthbetween the filter media pack inlet flow face and the filter media packoutlet flow face; and (c) a housing seal.
 73. An air filter cartridgeaccording to claim 72 wherein: (a) the resin jacket extends at least 90%of the length between the filter media pack inlet flow face and thefilter media pack outlet flow face.
 74. An air filter cartridgeaccording to claim 72 wherein: (a) the resin jacket extends at least 95%of the length between the filter media pack inlet flow face and thefilter media pack outlet flow face.
 75. An air filter cartridgeaccording to claim 72 wherein: (a) the resin jacket extends at least 98%up to 100% of the length between the filter media pack inlet flow faceand the filter media pack outlet flow face.
 76. An air filter cartridgeaccording to claim 72 wherein: (a) the cured-in-place resin jacketcomprises a spray coated cured-in-place resin jacket.
 77. An air filtercartridge according to claim 72 wherein: (a) the cured-in-place resinjacket comprises a molded cured-in-place resin jacket.
 78. An air filtercartridge according to claim 72 wherein: (a) the housing seal ismolded-in-place around the filter media pack.
 79. An air filtercartridge according to claim 72 wherein: (a) the housing seal ismolded-in-place around the cured-in-place resin jacket.
 80. An airfilter cartridge according to claim 72 wherein: (a) the housing seal ismolded-in-place adjacent to one of the filter media pack inlet flow faceor the filter media pack outlet flow face.
 81. An air filter cartridgeaccording to claim 72 wherein: (a) the housing seal is molded-in-placespaced from the filter media pack inlet flow face and the filter mediapack outlet flow face.
 82. An air filter cartridge according to claim 72wherein: (a) the combination of the fluted sheet and the facing sheetcomprises a lead end and a tail end, and the tail end is sealed by thecured resin jacket.
 83. An air filter cartridge according to claim 72wherein: (a) the inlet flow face and the outlet flow face have generallyflat surfaces.
 84. An air filter cartridge according to claim 81wherein: (a) the inlet flow face and the outlet flow face are parallel.85. An air filter cartridge according to claim 72 wherein: (a) thefilter media pack comprises the fluted sheet and the facing sheet in acoiled arrangement.
 86. An air filter cartridge according to claim 85further comprising: (a) a mold-in-place center within the coiledarrangement.
 87. An air filter cartridge according to claim 85 wherein:(a) the coiled arrangement has a circular perimeter shape.
 88. An airfilter cartridge according to claim 85 wherein: (a) the coiledarrangement has a perimeter shape with opposite curved ends and oppositesides.
 89. An air filter cartridge according to claim 88 wherein: (a)the filter media pack opposite sides are straight and parallel.
 90. Anair filter cartridge according to claim 72 wherein: (a) the housing sealincludes opposite axially directed surfaces separated by a peripheralsurface.
 91. An air filter cartridge according to claim 90 wherein: (a)the opposite axially directed surfaces of the housing seal are flat andparallel surfaces.